downsizing - need advice

We just downsized from a 41' toy hauler fifth wheel to a 36' Class A gas. Ours has one AC unit. We are in Oregon where it is hot only for one week out of the year. But, we are heading to Phoenix and Dallas in the spring and summer so we'll find out if one AC is enough.

Based on my own personal experience, a single AC will do an adequate job on a typical rig up to about 28 feet long in a hot and humid environment. Any larger, and you probably need a second AC. Of course each rig has it's own peculiarities such as insulation type and thickness, single pane/dual pane windows, etc that come into play.

You may need to add an oscillating fan to move the cool air around.

It depends on how big the Aspect and what "comfortable" means to you.

My similar construction Spirit is 30 foot, all white (not painted like an Aspect) and has a single 15K BTU air conditioner. On hot humid days it the shade, the A/C can pull interior temperatures down to 20-25 F below what it is outside. Thus 80-85 degrees on a 105 F day.

But in full sunlight, I might not see temperatures much below 90 F, from about noon to 3PM, when the lowering sun starts reducing that part of the heat load.

The second part: when it is that hot outside, I find 80-85 F comfortable. It is the temperature at which I also keep house in summer, when temperatures rise into the hundreds, and where I kept the house in summer when I lived in central Florida.

My M-I-L liked to cool her house (in Michigan) down to 70 F, dressing for winter year round. She would not be comfortable in my house or motorhome. Kind of funny, because she grew up in Louisiana many years before air conditioning and did not think of the 80s as hot until she lived in the North for many years.

If you end up with a 30ish foot Class C a single 13,500 BTU AC is going to struggle to reduce the outside temps by 20 degrees. In this scenario the question quickly becomes: How hot will it be where you are? Keep in mind that the misery index will rise dramatically with the humidity.

There are a number of tricks to help your AC. Chill the coach down early in the day. At Zion in June it was 100+ degrees every afternoon. We kept the shades pulled, a sun screen in the windshield and the curtain separating the cab from coach in place. Our 13,500 managed to keep our 24' C a pleasant 75-80 but it was really working.

I would not buy any C over 27' that only had a single 13,500. A 15,000 BTU unit will be better and anything over 30' really is getting into the two (13.5's), range.

Permit me a little misdemeanor thread drift and bring up the other side of the equation: heating. Before you buy, consider the size of the furnace, number of ducts and their location. I have seen a lot of rigs with woefully inadequate heating. Our 24' C has a 35,000 BTU, 4 duct (they are down low just a few inches above the floor), monster that keeps us toasty in any weather. Also know that the DC fan on your furnace will be the biggest load in your coach. If you don't have at least a pair of decent batteries your furnace run time will be limited. Also, furnaces burn a lot of propane so be sure you have sufficient capacity. Small rigs with LP generators typically have a very limited supply of LP when off the grid.

If you cannot be comfortable in just about any weather using your coach will not be fun.

As always.... Opinions and YMMV.

:C

I bought a 34 foot FW about ten years ago and decided to skip the second AC unit. Our first trip was to the Florida Panhandle and we got a site in the middle of an open field. The outside temperature was near 100 degrees and the temperature inside the unit was at least that. The thermostat maxed out at 100, so we don't know the actual temperature.

I set up the RV, turned on the AC unit and we went to dinner. We came back three hours later and the inside temperature was still in the mid 90s. The AC didn't start cycling until about 4:00 a.m. the next morning. It would run constantly after about 10:00 p.m. and couldn't keep up with the sun and humidity.

I took it in and had a second unit installed as soon as I got back. I miss having the roof vent in the bedroom, but the second AC is really a necessity down here.

Had a 26A, 2008 Winnebago Aspect with one slide, U-shaped dinette...

A/C, 13,500 in August got it to 82 degrees most days. Also used a tower
oscillating fan. It was just OK. Depends on what you consider comfortable.
This was outside of Tampa.

We did OK.

Our A/C is good until the outside gets above about 90. Above that it runs all the time and keeps the inside just bearable. We were in 100 degrees a couple of times, and it wasn't comfortable. All our previous units were travel trailers, and they were better in the heat.

mabynack wrote:
I bought a 34 foot FW about ten years ago and decided to skip the second AC unit. Our first trip was to the Florida Panhandle and we got a site in the middle of an open field. The outside temperature was near 100 degrees and the temperature inside the unit was at least that. The thermostat maxed out at 100, so we don't know the actual temperature.

I set up the RV, turned on the AC unit and we went to dinner. We came back three hours later and the inside temperature was still in the mid 90s. The AC didn't start cycling until about 4:00 a.m. the next morning. It would run constantly after about 10:00 p.m. and couldn't keep up with the sun and humidity.

I took it in and had a second unit installed as soon as I got back. I miss having the roof vent in the bedroom, but the second AC is really a necessity down here.

13500 or 15000?

Ducted or non-ducted?

I had a 35Ft fifth Wheel with one A/C. It could not do the job in Austin, TX at all. If it was 100 degree outside, it was 85 degree inside. I bought a second A/C to help cool it off, but it was loud and it could never get the temp down to 72 degree on days that were over 100 degree.